Dipped beam fault Custom Trend 2014

[sasquatch22]

hi everyone & thanks for letting me onto this forum
did anyone find a fix for this as its just happened on my transit custom 2015.
started intermitant and now its off alltogether and the dipped beam fault comes on as soon as i put the key in...tia

[k9robert]

hi all
My 2014 Custom has developed this problem also, on inserting the ing. key i get Dipped Heading bulb fault, my mechanic spent hours last night trying to find the fault to no avail.
Did find the plug that fits to the headlight with multi wires that there was no power to number eight on the block! check all the fuses but cant find a blown one, are there any other fuses other than the ones under the steering wheel.
Its just the drivers side, we swopped the headlight unit t the nearside and it worked perfectly so it seems to be this number eight wire fault!
Any help would be very welcome .
thanks

[KevofCov]

Same problem with my van. I'm guessing its a software issue.
I got a message on my dash and saw the bulb fail (night time). A couple of seconds later the lamp lit up again and I thought I back to normal! The next night it was out and the message had returned. Today I removed the bulb and the filament was broken.
This thread is on the same problem

viewtopic.php?f=65&t=209072&p=1744340#p1744340

[KevofCov]

A clue I think, lifted from a focus ST forum


The lighting on the ST, regardless of trim level is controlled by the BCM (body control module). The BCM uses what is referred to as FET (field affect transistor) to prevent damage to the module while controlling a 12 volt function. If the BCM determines that there is a change in voltage, it will shut down the FET and the light will not longer work. When this occurs, the BCM will network a message to the IC (instrument cluster) for a driver visible warning. At the same time, it will set a DTC for the corresponding light and which fault it detected, open, short, high voltage, low voltage, etc.

Long story short, you can replace a faulty light component 100 times but if you don't clear the code, the BCM will never know to resume normal operation.

This should of been taken to the dealer. No offense. These arn't your ma and pa kinda cars anymore, they are complicated.

My Forscan doesn't appear to be able to clear the fault....
Also how does this system comply with EU law that you should be able to change bulbs at the roadside....

[Altransit]

A clue I think, lifted from a focus ST forum.....................

Also how does this system comply with EU law that you should be able to change bulbs at the roadside....

Yet strangely, when this happened on my Focus, replacing the headlamp bulb reset the system with no diagnostics involved, and the bulb just worked. There could possibly still be a historic DTC in the system, but it has not caused any further problem It's hard to believe that, given the above law, that they can make replacing a bulb so complicated.

Is it possible that the blown bulb has created a fault/short somewhere in the connectors or the wiring?

[KevofCov]

A clue I think, lifted from a focus ST forum.....................

Also how does this system comply with EU law that you should be able to change bulbs at the roadside....

Yet strangely, when this happened on my Focus, replacing the headlamp bulb reset the system with no diagnostics involved, and the bulb just worked. There could possibly still be a historic DTC in the system, but it has not caused any further problem It's hard to believe that, given the above law, that they can make replacing a bulb so complicated.

Is it possible that the blown bulb has created a fault/short somewhere in the connectors or the wiring?

Yes I've had this before and all I did was change a good bulb for another good bulb. This fxed it... I'm going to visit a ford dealer and get a ford bulb - recommended by ford build to ford specs etc
Full report next week.

[KevofCov]

New bulb did nothing. £6 down.

[KevofCov]

Hi all
The following is my findings on the dipped beam not working issue.
I think that the following is spot on;

The lighting on the ST, regardless of trim level is controlled by the BCM (body control module). The BCM uses what is referred to as FET (field affect transistor) to prevent damage to the module while controlling a 12 volt function. If the BCM determines that there is a change in voltage, it will shut down the FET and the light will not longer work. When this occurs, the BCM will network a message to the IC (instrument cluster) for a driver visible warning. At the same time, it will set a DTC for the corresponding light and which fault it detected, open, short, high voltage, low voltage, etc.

Long story short, you can replace a faulty light component 100 times but if you don't clear the code, the BCM will never know to resume normal operation.

Yesterday I was able to clear the fault code using Forscan and all is back to normal. Two weeks ago I could not clear it.
When it has happened previously I put it down to cheap bulbs because fitting a Halfords bulb cured it where as a good cheap bulb didn’t.
The only remaining question is, is the problem a software /BCM issue or is the system just fine and it is only doing its job – there is a genuine wiring problem and it is only reacting to it?

[KevofCov]

Hi all
The following is my findings on the dipped beam not working issue.
I think that the following is spot on;

The lighting on the ST, regardless of trim level is controlled by the BCM (body control module). The BCM uses what is referred to as FET (field affect transistor) to prevent damage to the module while controlling a 12 volt function. If the BCM determines that there is a change in voltage, it will shut down the FET and the light will not longer work. When this occurs, the BCM will network a message to the IC (instrument cluster) for a driver visible warning. At the same time, it will set a DTC for the corresponding light and which fault it detected, open, short, high voltage, low voltage, etc.

Long story short, you can replace a faulty light component 100 times but if you don't clear the code, the BCM will never know to resume normal operation.

Yesterday I was able to clear the fault code using Forscan and all is back to normal. Two weeks ago I could not clear it.
When it has happened previously I put it down to cheap bulbs because fitting a Halfords bulb cured it where as a good cheap bulb didn’t.
The only remaining question is, is the problem a software /BCM issue or is the system just fine and it is only doing its job – there is a genuine wiring problem and it is only reacting to it?

Meant to say that my van is 2016 2.2 lwb 3.5t

[k9robert]

my 2014 custom does it every now and then, take it to an auto electrician who clears the fault codes , another £20 spent.
Why cars/vans nowdays have to be so complicated .